The invention relates to a device comprising semiconductor elements and conductor tracks of an oxidic superconductive material, electrically conductive connections being formed between the semiconductor elements and the conductor tracks, the electrically conductive connections comprising at least one antidiffusion layer. If desired, the electrically conductive connection may be formed only by the antidiffusion layer.
The invention also relates to a method of manufacturing such a device.
In an article by M. Gurvitch and A. T. Fiory in Applied Physics Letters 51 (13), pages 1027 to 1029 (1987) a method is described of manufacturing of thin layers of the oxidic superconductive compound YBa.sub.2 Cu.sub.3 O.sub.7 in accordance with a pattern on various substrates, such as silicon. With most of the substrates it was found that an antidiffusion layer is necessary. To this end, not only were electrically insulating layers investigated but also electrically conductive antidiffusion layers, such as layers of Ag, Nb and Cu. Moreover, their application to silicon substrates did not have the desired result because of the poor adhesion of the layers and because the oxidic compound did not exhibit superconductive behaviour at the desired temperatures (exceeding 77.degree. K.).
Substrates to which oxidic superconductive materials can be applied with good results are in general insulating oxidic materials, such as MgO, ZrO.sub.2 and SrTiO.sub.3, and noble metals such as gold and silver. Gold and silver can be used to form electrically conductive connections. However, these metals are not very suitable for use as a diffusion barrier. Gold is less suitable for use in contact with semiconductor devices owing to the possible formation of a Si-Au eutectic composition at a low temperature. Silver is unsuitable because of the high diffusion rate of silver itself.
Antidiffusion layers for use in semiconductor devices must meet a number of requirements. In semiconductor technology, for example, protective layers of Si.sub.3 N.sub.4 are used which are applied at a temperature of 450.degree. C. At this temperature no undesired reactions must occur in and between the previously applied layers. At this temperature oxidation of the antidiffusion layers must not occur either.